The present invention generally relates to a non-stop device having load-bearing rods and a method for using the device.
Various forms and designs of such devices are known and in use. For example, with punching machines for paper and cardboard sheets, it is desirable for increasing the output to be able to exchange without interruption pallets of sheet piles or so-called stack of blanks so as not to interrupt the remaining production process when exchanging the pallets. For this purpose, it is possible to provide a delivery station, in which the sheets or blanks are first stacked into a pile. When a specific height is achieved, the pallet with the stack has to be exchanged. A non-stop device has the purpose of temporarily accepting the sheets or blanks during the exchange of pallets so that production does not have to be stopped during this process.
For example, the non-stop device can also be provided when a division sheet has to be inserted in order to form stable stacks of separate sheets or blanks on the pallet of the delivery station.
Such a non-stop device has been disclosed in the DE 601 02 097 T2. It comprises a carriage movable in the longitudinal direction of the press. The carriage has two cross beams on which a plurality of load-bearing rods may be arranged to form a so-called rake for the non-stop delivery of sheets or blanks. For the purpose of inserting division sheets, the carriage moves underneath a lower blank separating tool and a pair of load-bearing rods catches each dropping sheet or blank. The non-stop device temporarily receives the blanks that are stacked during the process of inserting the division sheets.
However, this method has the disadvantage that the process of positioning the rods is complicated and time-consuming because not only do the load-bearing rods have to be placed on the movable carriage, but they also have to be centered and clamped to ensure that the sheets or blanks to be caught are adjusted correctly. This presents an additional complication for the design of the non-stop device.
The prior art also includes the method of inserting so-called non-stop rods manually. For this purpose, rods are inserted in respectively provided openings. This is done manually. Subsequently, a tool has to be used to fix each individual rod with a retaining screw. This is also done manually. The fact that each of these steps is performed manually results in deviations with regard to the tightness of the rods. This, in turn, results in the problem that rods tightened by one user can only be unscrewed with a disproportionate amount of effort by a different user. Moreover, the weight put on the rods by the sheets or blanks can result in deadlocks in the screw threads which results in the fact that unscrewing the rods is even more time-consuming. With this method known from prior art, the machines have to be stopped frequently, resulting in production losses. Furthermore, this method requires that each load-bearing rod has to be removed individually. Consequently, depending on the size and weight of the sheets or blanks, it is possible that at the places where the load-bearing rods have already been removed the sheets or blanks are sagging and, as a result, are being damaged. Quick removal is impossible. Other sources of mistakes involve misplacing of tools or inadequately trained personnel.